Tap the "Google Maps" icon on your smartphone's screen to launch the app.
Tap "Search" and type an address or a city in the search field. Tap "Search" again.
Touch the phone's display with two fingers and pinch outward to expand the image, or tap the map repeatedly to zoom in. The map stays in vertical portrait mode even if you rotate the phone, with one exception -- the updated version of the Google Maps app for Android has an option that lets you tap the "Compass" icon at the top of the screen to enable map rotation as you rotate the phone. Do not tap this icon if you want Google Maps to stay fixed in vertical portrait mode.